Formation of mesostructure compositions based on refractory compounds for friction pairs (a review)

The creation of mesostructural compositions for friction pairs made of cemented carbide based on WC and TiC carbides is presented. The class of mesoelement will determine the features of sintering of the mesocomposition. For friction pairs, mesocompositions of the first and second classes based on carbides of refractory compounds are suitable, and in this case, for mesocompositions of the first class, solid-phase sintering under pressure must be used to prevent rapid decay of the granules of mesoelements, while for mesocompositions of the second-class liquid-phase sintering is sufficient. The dependence of the crack growth resistance and wear resistance on the volume content of binding metal and mesoelement granules in the composition and their influence on the extent of residual thermal stresses, which are lower compared to homogeneous cemented carbides, is demonstrated. The influence of alloying elements such as Cr₃C₂ and Mo₂C on mesoelements and mesostructure formation during liquid phase sintering is highlighted. The necessity of using a nickel binder for the manufacture of friction pairs based on WC and TiC carbides for operation in nuclear reactor turbines is substantiated.